Extracorporeal shock wave lithotripsy: interventional radiologic solutions to associated problems.

Among 1,500 patients treated with extracorporeal shock wave lithotripsy, 1,300 had calculi less than 2.5 cm in diameter and 200 had calculi of 2.5 cm or larger. Although most patients did well and required no further radiologic intervention, 178 interventional radiologic procedures were performed. Urinary tract obstruction often developed in patients with large stones when the collecting system filled with stone fragments (steinstrasse). Nephrostomy was performed in 5.3% of the total patient population and in 29% of the patients with stones measuring 2.5 cm or more. Only 1.8% of the patients with calculi smaller than 2.5 cm required radiologic intervention. When the obstructed collecting system could not be crossed with conventional angiographic techniques, the stone fragments were removed through a percutaneous nephrostomy tract either by flushing or by suctioning with a pulsating water jet.